Hydraulic aircraft/stores cartridge

Abstract

A hydraulic cartridge suitable for releasing stores in aircraft relies on aressurized piston rod which extends upon release of hydraulic pressure. The piston rod is enclosed in a cylinder and connected to a source of hydraulic fluid. Upon arming of the piston rod a hydraulic liquid is pumped into the piston rod and forces out a gas via an accumulation piston. Upon complete filling of the piston rod, a trigger is held in place by the pressurized fluid. Upon release of pressure, the pressure on the trigger becomes unbalanced and a spring releases the trigger from the piston rod permitting it to extend.

What is claimed is: 
     
       1. A hydraulic cartridge comprising: a cylinder;   a cylinder cover attached to said cylinder for enclosing a fixed volume between said cylinder and said cylinder cover;   a cylinder cap attached to said cylinder for limiting access of a first fluid to said cylinder except through said cylinder cap;   a piston including a piston rod slideably mounted within said cylinder for extending from said cylinder upon occurrence of specific events;   a tube mounted within said piston, a passageway for passing fluid entering said cylinder cap the length of the piston rod before the first fluid can exit said passageway and enter said piston rod; an orifice in said piston rod;   an accumulator piston slideably mounted within said piston rod and around said tube for compressing a second fluid of preset pressure within said piston rod for forcing said second fluid out of said orifice when said first fluid enters said piston rod;   a means for triggering said piston rod to extend from said cylinder;   means for charging said second fluid in said piston rod to a preset pressure level; and   means for pressurizing said piston rod with said first fluid, where said pressurizing means comprises: a valve with three positions connected to the cylinder cap for setting the first fluid's state in said cylinder and piston to either a "safe", an "arm", or a "fire" state;   a fill port connected to said valve via the "arm" position for filling said piston rod with the first fluid to a desired pressure level;   a sump connected to said valve via the "fire" position for providing a discharge path for said pressurized first fluid in said piston rod; and a restricted orifice passageway connected between the "safe" position of said valve and said sump for bleeding any pressure build-up from said piston rod when the piston rod is not to be triggered.     
     
     
       2. A hydraulic cartridge as described in claim 1 where said triggering means comprises: a plurality of latches mounted on the internal end of said piston rod; and   a spring loaded trigger inserted in said latches and said cylinder cap for locking said latches to said cylinder such that said piston rod cannot extend from said cylinder until said trigger compresses the spring releasing said latches.